Effects of alcohol on the upper gastrointestinal tract and the pancreas - An up-to-date overview

The oesophagus, stomach and pancreas are primary target organs for ethanol-related diseases. In the oesophagus and stomach, ethanol induces motility disorders and mucosal lesions that are dose-dependent and reversible under acute conditions. Chronic consumption of alcohol causes a significant increase in the risk for squamous carcinoma of the oesophagus. All of these effects are mainly caused by direct contact of alcohol or its metabolite acetaldehyde with the mucosa. Non-alcoholic components are responsible for many effects of alcoholic beverages, including the powerful stimulation of gastric acid secretion by beverages that are produced by fermentation. In the exocrine pancreas, alcohol induces secretory alterations that are mainly affected by the manner and duration of alcohol exposure, the additional administration of food, the type of beverage or the basal secretory state of the gland. Because the pancreas is not topically exposed to ethanol, these ethanol effects on pancreatic secretion are primarily caused by systemic cholinergic mechanisms of the vagus nerve. Chronic alcohol abuse may cause chronic alcoholic pancreatitis after recurrent subclinical inflammatory episodes. Genetic predispositions are believed to play an additional role in the pathomechanism of the disease. In contrast to the cardiovascular system, moderate consumption of alcoholic beverages does not have any beneficial health effects on the oesophagus, stomach or pancreas. Future research needs to define the exact molecular mechanisms and the role of different genetic predispositions for alcohol-induced diseases as well as the effects of the non-alcoholic components of alcoholic beverages.